Avijarna influenca kod divljih ptica u Pokrajini Vojvodini 2020-2022

Abstract

Avian influenza (AI) or “bird flu” is highly contagious viral disease caused by avian influenza viruses type A (AIV). The AIV primarily infects wild birds, but the virus can affect also domestic poultry causing enormous economic loses. Avian influenza is a zoonotic disease, although human infections are rare, there have been recorded severe complications with fatal outcome. Based on the molecular characterization and upon the severity of clinical signs in poultry, avian influenza viruses are classified into: highly pathogenic avian influenza (HPAI) and low pathogenic avian influenza (LPAI) viruses. The first incursion of HPAI H5N1 was detected in Serbia in mute swans in 2006, followed by epidemics in 2016/2017. Since then, AIV is circulating in this region and poses a threat for human health. The aim of this study was to investigate the presence of AIV in various wild birds which represent the reservoir of AIV, in the water habitats of the Vojvodina Province (Serbia), as well as to determine their importance in virus dissemination in the region. In total, 610 samples from wild birds were collected from the 1StNovember 2020 till 31st March 2022, during the IPA cross-border project Hungary-Serbia and Monitoring program of Avian influenza in poultry and wild birds in Republic of Serbia, that was launched by the Veterinary Directorate of RS. The sampling territory encompasses aquatic landscapes in the special nature reserves, hunting grounds and river coasts in the Vojvodina Province. The specimens represented: cloacal swabs, tracheal swabs, bird carcasses of found dead or shot birds and pooled faeces from the coastal areas. The samples belonged to 56 different bird species. For detection of AIV genome was used real-time RT-PCR to determine matrix gene (M), and H5 and H7 subtypes. Laboratory analyses confirmed the presence of AIV RNA in 18 out of 610 tested samples (2.95%, 18/610). The AIV genome was identified in three waterfowl bird species (mallard duck, mute swan and gull), collected from 10 different locations. The results of our research have proven the presence of AIV in wild birds in Voјvodina Province. Furthermore, it is necessary to implement continuous surveillance program for the protection of public health against the new emergency of AIV in future.